Electric switch



1950 c. HALL suzc'mlc swn'ca rim Oct. 22, 1945 Inventor: Chester Hall.

4 I g I I I I z His Attorney. I

Patented July 4, 1950 ELECTRIC SWITCH Chester I. Hall, Vischers Ferry, N. Y., assignor to General Electric Company, a corporation of New York Application October 22, 1945, Serial No. 823,650 3 Claims. 200-87) My invention relates to electric switches, more particularly to electromagnetically operated switches of the type known as contactors. and has for its object a simple and reliable shockproof electromagnetic operating means.

In carrying out my invention in one form I operate the movable switch contact by means of a plunger armature having a rack on one end which engages a pinion. The pinion is connected to a crank which, in turn, is connected by means of a link to a switch operating lever. I also provide a second rack mounted for slidable movement in a direction parallel with the movement of the first rack and engagin the pinion on a side opposite the first rack. This second rack is constructed to have a weight equal to the weight of the first rack and the armature combined so that the second rack acts as a counterbalancing weight, thereby making the armature and first rack free from shocks. Moreover, the mechanism is so arranged that the crank is moved from one dead center to another upon movement of the plunger, whereby the operating lever is secured in each position against the effect of shocks.

For a more complete understanding of my invention, reference should be had to the accompanying drawing, Fig. 1 of which is a side elevation view, partly in section, of a contractor embodying my invention shown in its open position; Fig. 2 is a front elevation view, partly in section, of the device shown in Fig. 1; Fig. 3 is a sectional view along the line 3-3 of Fig. 1 looking in the direction of the arrows. while Fig. 4 is a fragmentary view of the operating mechanism showing the parts in their contactor closed positions.

Referring to the drawing, I have shown my invention in one form as comprising an electrically insulating support I on which are mounted two spaced apart stationary contacts 2 and 3 with which cooperates a movable bridging contact member 4' mounted on an operating lever 5 having a stationary pivot 6. The lever 5 is mounted on a U-shaped, or channel-shaped, metal supportin member 1 having its base wall secured to the panel support I. Likewise, the lever 5 is U-shaped, or channel-shaped, as shown clearly in Fig. 3, with its side flanges fitting loosely between the sides of the support I and pivoted thereto by a pivot 6 on each side.

Mounted between the side flanges of the support I at its upper end is a magnet frame 8 provided with an operating coil 9 and with a plunger armature l0 arranged for movement in a substantially vertical direction. On the lower end of the armature I0 is secured a rack H extending longitudinally of the armature, the upper end of the rack being secured on a, pivot i2 between the two projections of the forked lower end of the armature.

For operation of the lever 5, the rack H meshes with a pinion or gear [3 secured on a shaft H mounted at its ends on bearings i5 and I6 secured to the sides of the support I, the shaft I4 extending parallel with the panel I and at right angles to the direction of movement of the armature III. A second shaft I 1 parallel with the shaft H is provided on the opposite side of the rack II, this shaft being provided with a guide roller l8 engaging the opposite straight side of the rack I I so as to hold the rack in meshing relation with the pinion. Also secured to the shaft [4 is a crank l9 having a crank pin 20 which is connected by a link 2| to a pivot pin 22 on the lever 5.

The operating parts are so arranged that when the plunger is-in its lowermost unattracted position, as shown in Figs. 1 and 2, in which it rests against a suitable stop (not shown), the crank pin 20 is in a substantially dead center position with respect to the pin 22. In other words, the centers of the two pins and of the shaft [4 lie substantially on a straight line. When the plunger is moved upward, u-pon energization of the coil 9, to its attracted position against a suitable stop (not shown) the crank I9 is turned substantially through a degree angle substantialiy to its opposite dead center position, as shown in Fig. 4. Therefore, in each of its posi tions the crank holds the operating lever 5 securely whereby the operating lever is free from the effects of shocks. Preferably, however, for maximum shockproofness the crank is turned. through an angle somewhat greater than 180, for example so that the crank is turned slightly beyond its dead center position in each direction.

I have also provided a second and weighted rack 23 engaging the pinion I! on its side opposite the rack It for the purpose of counterbalancing the weight of the plunger l0 and the rack H, thereby to render the plunger l0 and rack ll free from the eflects of shocks applied to the device. This counterbalancin g rack 23 is secured to and includes a weight bar portion 24 which is mounted in uides 25 and 26 secured to the back wall or base of the support 1. Byv

means of these guides the rack 23 including the bar 24 is mounted for straight line movement a in parallel relation with the direction of movement of the armature l0. a helical tension spring 21-biases the rack 23 to its uppermost position with the armature in its lowermost position as shown in Fig. 1. This spring extends through a longitudinal slot 28 in the bar portion, 24 and has its upper end secured to a pin 29 mounted on the support I and its lower end secured to a pin 30 mounted on the lower end of the bar portion 24. It will be observed that this spring 21 is the means for biasing-the operating lever to its open circuit position.

As shown, the bridging contact 4 is mounted on a springstrap 3| which extends through a slot 32 in a projection 33 on the upper end 01' the lever B and downward lengthwise of the lever to a point adjacent the lower end of the lever where the strap is provided with a right-angle proiection 34 engaging the lever. By means of a screw 35 extending through the strap, the strap may be given a curvature or bias between the points 33 and 34, thereby to adjust the spacing between the bridging member 4 and the stationary contacts when the contactor is in its open circuit position and the amount of wipe between the bridging member and the stationary contacts.

While I have shown a particular embodiment 01' my invention, it will be understood, 01 course, that I do not wish to be limited thereto since many modifications may be made and I therefore contemplate by the appended claims to cover any such modifications as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A shockproof electric switch comprising a support, a magnet frame fixed to said support, a coil on said frame, a plunger armature for said coil mounted for movement in a, substantially vertical'direction between attracted and unattracted positions, a first movable rack fixed to said armature for movement therewith, a, pinion engaged by said rack, a crank connected to said pinion moved by said armature from one dead center position to another, a second movable rack slidably mounted on said support and engaging said pinion on its side opposite said first rack. said second rack being mounted for movement in a direction substantially parallel to the direction of movement of said first rack and having a weight counterbalancing the weight 01' said armature and said first rack, a switch operating lever, a link connecting-said crank with said lever so as to move said lever between closed and open circuit positions upon rotation of said crank substantially between its said dead center positions, a spring connected to said second rack for biasing said armature to its unattracted position. and electric switch means connected to said operating lever.

2. A shockproot electric switch comprising a s pp r a first movable rack slidably mounted on said support, actuating means connected to drive said first rack, a pinion rotatably mounted on said support and engaging said first rack to be driven thereby, a crank connected to said pinion and movable through at least from one dead center position to another, a second movable rack slidably mounted on said support and engaging said pinion on the side opposite said first movable rack, the weight of said second rack counterbalancing the weight of said first rack, a movable switch member, and a link connecting said crank with said switch member to move said switch member between closed and open circuit positions each corresponding to one of said dead center positions.

3. A shockprooi' electric switch comprising a support, a first movable rack slidably mounted on said support for movement in a substantially vertical direction, actuating means connected to drive said first rack, a pinion rotatably mounted on said support and engaging said first rack to be driven thereby, a crank connected to said pinion and movable thereby through at least 180 from one dead center position to another, a second movable rack slidably mounted on said support for movement substantially parallel to the direction of movement of said first rack and engaging said pinion on the side opposite said first rack, the weight of said second rack counterbalancing the weight of said first rack, a movable switch operating member, and a link connecting said crank with said switch member to move said switch member between open and closed circuit positions upon rotation of said crank substantially between its said dead center positions.

CHESTER I. HALL.

REFERENCES crrEn The following references are of record in the file of this patent: 

